Flexible high performance inorganic matter fet using built-in strain of inorganic matter on insulator wafer

ABSTRACT

Provided is a method for manufacturing an inorganic material having a tensile stress, which includes: forming an inorganic stressor from an inorganic wafer made of an inorganic matter; forming an inorganic layer on the inorganic stressor; and etching a bulk inorganic matter at a lower portion of the inorganic stressor to generate an inorganic material having a tensile stress, wherein the inorganic layer has a tensile stress by etching the bulk inorganic matter to relieve a compressive stress applied to the inorganic stressor when the inorganic stressor is being formed. Therefore, FET and various circuits having higher charge mobility may be realized, and also, since characteristics may be maintained even when being applied to a plastic substrate, high performance flexible electronic device may be manufactured.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a divisional application of U.S. application Ser.No. 15/099,198, filed Apr. 14, 2016, and claims priority under 35 U.S.C.§ 119 to Korean Patent Application No. 10-2015-0053018 filed on Apr. 15,2015 in the Korean Intellectual Property Office, the disclosure of whichis incorporated herein by reference in its entirety.

TECHNICAL FIELD

The following disclosure relates to a method for manufacturing a devicebased on an inorganic semiconductor such as silicon, a compoundsemiconductor, an oxide semiconductor or the like, and in particular, toa method for manufacturing an inorganic material having a tensile stressby using built-in strain of an inorganic wafer, a material manufacturedby the method, and a device based on the material.

BACKGROUND

In order to enhance charge mobility of a silicon semiconductor, existingsemiconductor companies and various research groups have attemptedvarious methods, and as a representative method, silicon is grown on asilicon-germanium alloy with a crystal lattice constant. If this methodis used, a significant amount of tensile stress is applied to a siliconthin film due to lattice distortion of silicon-germanium and silicon,and resultant improvement of charge mobility may be expected. However, asilicon-germanium, also silicon thereon, should be grown againdifficultly, and complex processes and great costs are also problems.

In case of an existing silicon-based flexible field effect transistor(FET) prepared on a flexible substrate such as an existing plastic orrubber substrate, a silicon oxide (SiO₂) sacrificial layer is etchedfrom a silicon thin film wafer formed on an insulator in asilicon-on-insulator (SOI) wafer in order to separate the silicon thinfilm, and is transferred onto a flexible substrate. In this method,since silicon oxide at a lower portion is used as a sacrificial layerfor etching, compressive stress present in the silicon oxide is removedwhile silicon is being separated. Also, since silicon at an upperportion is suspended in a suspended state, no stress is applied.Therefore, improvement of charge mobility caused by a strain rate is notexpected.

RELATED LITERATURES Patent Literature

Korean Unexamined Patent Publication No. 10-1999-0045409, entitled“Method for manufacturing a silicon gate FET”

SUMMARY

An embodiment of the present disclosure is directed to providing amethod for manufacturing an inorganic semiconductor material, such assilicon, a compound semiconductor, an oxide semiconductor or the like,having a tensile stress without a buffer layer by using built-in strainof an inorganic wafer.

The present disclosure is also directed to providing a semiconductordevice having improved electric characteristics, which includes aninorganic material having a tensile stress without a buffer layer byusing built-in strain of an inorganic wafer.

In one general aspect, the present disclosure provides a method formanufacturing an inorganic material having a tensile stress, the methodcomprising: forming an inorganic stressor from an inorganic wafer madeof an inorganic matter; forming an inorganic layer on the inorganicstressor; and etching a bulk inorganic matter at a lower portion of theinorganic stressor to generate an inorganic material having a tensilestress, wherein the inorganic layer has a tensile stress by etching thebulk inorganic matter to relieve a compressive stress applied to theinorganic stressor when the inorganic stressor is being formed.

According to another embodiment of the present disclosure, the inorganicstressor may be formed by oxidizing or nitriding the inorganic wafer, orby depositing metal or dielectrics on the inorganic wafer.

According to another embodiment of the present disclosure, the methodmay further comprise forming a device on the inorganic stressor.

According to another embodiment of the present disclosure, the methodmay further comprise patterning the inorganic wafer on which theinorganic stressor is formed.

According to another embodiment of the present disclosure, the methodmay further comprise: detaching the inorganic material having a tensilestress from the inorganic wafer; and transferring the detached inorganicmaterial having a tensile stress to a substrate.

According to another embodiment of the present disclosure, the inorganicmatter may be an inorganic matter which allows oxidization andnitridation.

According to another embodiment of the present disclosure, a tensilestress of the inorganic layer may vary depending on thickness or kind ofthe inorganic layer and the inorganic stressor.

According to another embodiment of the present disclosure, in theetching of a bulk inorganic matter at a lower portion of the inorganicstressor to generate an inorganic material having a tensile stress, thebulk inorganic matter at the lower portion of the inorganic stressor maybe etched from an upper portion of the inorganic stressor.

According to another embodiment of the present disclosure, in theetching of a bulk inorganic matter at a lower portion of the inorganicstressor to generate an inorganic material having a tensile stress, thebulk inorganic matter at the lower portion of the inorganic stressor maybe etched from a lower portion of the inorganic stressor by means of dryetching.

In another aspect of the present disclosure, there is provided aninorganic material having a tensile stress, comprising: an inorganicstressor formed from an inorganic wafer made of an inorganic matter; andan inorganic layer formed on the inorganic stressor to have a tensilestress, wherein the inorganic layer has a tensile stress by etching thebulk inorganic matter to relieve a compressive stress applied to theinorganic stressor when the inorganic stressor is being formed.

According to another embodiment of the present disclosure, the inorganicstressor may be formed by oxidizing or nitriding the inorganic wafer, orby depositing metal or dielectrics on the inorganic wafer.

According to another embodiment of the present disclosure, the inorganicmaterial may be a semiconductor device having electric characteristicssuch as bandgap, or improved drain current, and charge mobility, by atensile stress generated by etching the bulk inorganic matter.

According to another embodiment of the present disclosure, the inorganicmaterial may further include a substrate located at a lower portion ofthe inorganic stressor.

According to another embodiment of the present disclosure, the inorganicmatter may be an inorganic matter which allows oxidization andnitridation.

According to another embodiment of the present disclosure, a tensilestress of the inorganic layer may vary depending on thickness or kind ofthe inorganic layer.

According to the present disclosure, an internal lattice receiving atensile stress may have an increased size so that electrons may movemore rapidly. Therefore, FET and various circuits having higher chargemobility may be realized. Also, since characteristics may be maintainedeven when being applied to a plastic substrate, high performanceflexible electronic material may be manufactured.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a flowchart for illustrating a method for manufacturing aninorganic material having a tensile stress according to an embodiment ofthe present disclosure.

FIG. 2 is a flowchart for illustrating a method for manufacturing aninorganic material having a tensile stress according to anotherembodiment of the present disclosure.

FIG. 3 is a flowchart for illustrating a method for manufacturing aninorganic material according to an embodiment of the present disclosure.

FIG. 4 is a flowchart for illustrating a method for manufacturing aninorganic material according to another embodiment of the presentdisclosure.

FIG. 5a is a diagram showing a process of etching an upper portion of abulk inorganic matter according to an embodiment of the presentdisclosure.

FIG. 5b is a diagram showing a process of etching a lower portion of abulk inorganic matter according to an embodiment of the presentdisclosure.

FIG. 6 shows an inorganic matter device having a tensile stressaccording to an embodiment of the present disclosure.

FIG. 7 is a diagram showing a process of analyzing a mechanism ofmanufacturing an inorganic material having a tensile stress andanalyzing a stress thereof according to an embodiment of the presentdisclosure.

FIG. 8a is a diagram showing locations of suspended silicon/siliconoxide ribbon and silicon/silicon oxide ribbon transferred onto the PETsubstrate according to an embodiment of the present disclosure.

FIG. 8b is a graph showing a Raman pick location of each locationaccording to an embodiment of the present disclosure.

FIG. 8c is a graph showing a changing amount of tensile stress accordingto the thickness of a top Si according to an embodiment of the presentdisclosure.

FIG. 8d is a graph showing the calculated and the measured values oftensile stress.

FIG. 9a is a diagram showing a manufactured inorganic matter devicehaving tensile stress and improved electric characteristics involving anoxidized silicon wafer according to an embodiment of the presentdisclosure.

FIG. 9b is a diagram showing the silicon FET ribbon being detached byusing a roller according to an embodiment of the present disclosure.

FIG. 9c is a diagram showing the sectional structure of the transferredsilicon FET device according to an embodiment of the present disclosure.

FIG. 10a shows a graph of electric characteristics of an inorganicmatter device having different tensile stresses according to anembodiment of the present disclosure.

FIG. 10b shows a graph of output characteristics of the silicon FET ofthe material according to an embodiment of the present disclosure.

FIG. 10c is a graph showing charge mobility of a material prepared basedon the obtained electric characteristic curve according to an embodimentof the present disclosure.

FIG. 11a shows an image of the automatic transferring machine and astructural front section of the automatic transferring machine.

FIG. 11b shows an image of broad-band flexible TET array located at thePET substrate.

FIG. 11c shows a histogram of mobility distribution measured from thebroad-band silicon FET array.

DETAILED DESCRIPTION OF EMBODIMENTS

Prior to the explanation of the present disclosure, solutions ortechnical spirit of the present disclosure will be summarized oressentially proposed for convenient understanding.

A method for manufacturing an inorganic material having a tensile stressaccording to an embodiment of the present disclosure includes: formingan inorganic stressor from an inorganic wafer made of an inorganicmatter; forming an inorganic layer on the inorganic stressor; andetching a bulk inorganic matter at a lower portion of the inorganicstressor to generate an inorganic material having a tensile stress,wherein the inorganic layer has a tensile stress by etching the bulkinorganic matter to relieve a compressive stress applied to theinorganic stressor when the inorganic stressor is being formed.

Hereinafter, embodiments of the present disclosure, which can be easilyimplemented by those skilled in the art, are described in detail withreference to the accompanying drawings. However, these embodiments arejust for better understanding of the present disclosure, and it will beobvious to those skilled in the art that the scope of the presentdisclosure is not limited to these embodiments.

The configuration of the present disclosure will be described in detailwith reference to the accompanying drawings based on the embodiments ofthe present disclosure to clearly understand the solutions of thepresent disclosure. Here, when any drawing is explained, a componentdepicted in another drawing may also be cited, if necessary. Moreover,when explaining an operation principle of an embodiment of the presentdisclosure, detailed explanation of any known function or configurationrelated to the present disclosure or other matters may be omitted if itmay unnecessarily make the essence of the present disclosure confused.

FIG. 1 is a flowchart for illustrating a method for manufacturing aninorganic material having a tensile stress according to an embodiment ofthe present disclosure.

An inorganic material according to an embodiment of the presentdisclosure has a tensile stress by relieving a compressive stressgenerated while an inorganic stressor is being formed from a wafer madeof the inorganic matter. Therefore, a material having a tensile stressmay be made without any separate buffer layer made of SiGe or the like,and the material may have improved performance. In order to give atensile stress to an inorganic material by using a compressive stressgenerated while an inorganic stressor is being formed from a wafer madeof the inorganic matter, the following processes are performed.

Step 110 is a step of forming an inorganic stressor from an inorganicwafer made of an inorganic matter.

In more detail, an inorganic stressor is formed from an inorganic wafermade of an inorganic matter. The inorganic stressor may be formed byoxidizing or nitriding the inorganic wafer, or depositing a metal ordielectrics on the inorganic wafer. In other case, various processes inwhich the inorganic stressor may have a compressive stress may be used.An oxidation process will be described below as a representativeexample.

An oxidized inorganic stressor is formed by oxidizing an inorganic waferat high temperature. While the inorganic stressor is formed throughhigh-temperature oxidation, a compressive stress is formed in theinorganic stressor. A residual stress is a stress generated in thematerial during a processing or thermal treatment process, and such astress is created by a result of irregular plastic deformation caused bycold working, tempering, welding or the like. The residual stress isclassified into a residual tensile stress and a residual compressivestress. Regarding the residual stress, the residual compressive stressgenerally appears at a surface, and the residual tensile stress isgenerated at an inside. In case of a stress generated by deformation, aresidual tensile stress appears at a surface, and a residual compressivestress is generated at an inside, contrary to the above. If surfacetempering such as carburizing or high-frequency tempering is performed,a residual compressive force is created at a surface layer.

If an inorganic stressor is formed by depositing a metal or dielectrics,the inorganic stressor may be formed by depositing a metal by means ofE-beam evaporation, thermal evaporation, sputtering or the like, or bydepositing dielectrics by means of CVD, PVD, ALD or the like.

Step 120 is a step of forming an inorganic layer on the inorganicstressor.

In more detail, an inorganic layer to be used as a material is formed onthe inorganic stressor formed in Step 110. The inorganic layer may beformed in various ways depending on the kind and shape of a material tobe manufactured.

Step 130 is a step of generating an inorganic material having a tensilestress by etching a bulk inorganic matter at a lower portion of theinorganic stressor.

In more detail, the bulk inorganic matter at the lower portion of theinorganic stressor is etched to generate an inorganic material having atensile stress. As the bulk material at the lower portion to which theinorganic stressor belongs is removed, the compressive stress isrelieved, and the inorganic layer receives a tensile stress, whichallows an inorganic material having a tensile stress to be generated.When the inorganic material receives a stress formed when oxidizing aninorganic wafer, as an internal lattice of the inorganic matterincreases, electrons may move more rapidly. By using the inorganicmaterial having a tensile stress generated as above, a field effecttransistor (FET) or various circuits having high charge mobility may berealized. Also, since characteristics may be maintained even when beingapplied to a plastic substrate, high performance flexible electronicmaterial may be manufactured.

In addition, the tensile stress of the inorganic layer may varydepending on thickness or kind of the inorganic layer and the inorganicstressor. The tensile stress varies depending on the kind of theinorganic layer or the inorganic stressor. In addition, the degree oftensile stress may be adjusted by controlling the thickness of theinorganic stressor or the inorganic layer formed on the inorganicstressor. The thickness of the inorganic stressor may be adjustedaccording to the degree of etching of the bulk inorganic matter at alower portion. As the inorganic layer has a smaller thickness, theamount of tensile stress is greater. Therefore, the thickness of theinorganic layer may be adjusted according to the degree of tensilestress of a material to be manufactured. It is also possible tomanufacture a material having a predetermined tensile stress byadjusting the kind, thickness and structure of the material.

FIGS. 2 to 4 are flowcharts for illustrating a method for manufacturingan inorganic material having a tensile stress according to anotherembodiment of the present disclosure.

Step 210 is a step of forming a device on the inorganic stressor.

In more detail, a device to be implemented by using an inorganic matteris formed on the inorganic stressor formed from the inorganic wafer. Thedevice may be formed after preparing the inorganic stressor by oxidizingthe inorganic wafer, or the device may also be formed before oxidizingthe inorganic wafer. When a FET is formed, a source, a drain and a gateare formed on the inorganic stressor. It is also possible to arrange aplurality of devices.

Step 310 is a step of patterning the inorganic wafer on which anoxidized inorganic stressor is formed.

In more detail, the inorganic wafer on which the inorganic stressor isformed may be patterned into a desired form. The patterning form mayhave a simple ribbon shape. After patterning into a ribbon shape, thebulk inorganic matter below the inorganic stressor may be etchedaccording to the pattern to form a suspended inorganic matter ribbon.

Step 410 is a step of detaching the inorganic material having a tensilestress from the inorganic wafer.

In more detail, the inorganic material formed on the wafer is detachedby using a polydimethyl siloxane (PDMS) roller or other equipment.Polydimethyl siloxane has various features. First, the PDMS may bestably adhered to a relatively broad area of the substrate. Thus, thePDMS may be satisfactorily applied to an uneven surface. Second, thePDMS has low interfacial free energy. Therefore, when another polymer ismolded using the PDMS, adhesion does not occur easily, thereby ensuringgood molding. Third, the PDMS is an elastomer with excellent durability.This may be figured out from experiments in which remarkable degradationdoes not occur even though a molded PDMS stamp is used several hundredtimes and for several months. Fourth, the surface property of the PDMSmay be easily modified by adjusting plasma generated by the formation ofself-assembly monolayers (SAMs), and this may appear over a broad rangeof interfacial energy due to suitable interfacial interaction betweensubstances. By using a roller made of polydimethyl siloxane (PDMS)having the above features, the inorganic material having a tensilestress is detached.

Step 420 is a step of transferring the detached inorganic materialhaving a tensile stress to the substrate.

In more detail, the detached inorganic material having a tensile stressis transferred to a substrate to be used. The inorganic material havinga tensile stress detached in Step 410 is transferred to the substrate tobe used, made of a semiconductor material or the like.

The used inorganic matter may be an inorganic matter which allowsoxidation and nitridation. Here, the inorganic matter may be silicon, acompound semiconductor, an oxide semiconductor or the like. In othercase, another material having an internal residual stress may also beused. A residual stress occurring at a silicon wafer (SOI wafer) formedon the insulator may be shifted to a suspended silicon ribbon togenerate a tensile stress and thus improve charge mobility. By doing so,a flexible FET based on high performance single crystal silicon may bemanufactured. When the silicon wafer (SOI wafer) formed on the insulatoris made, a residual stress is formed during a process of forming asilicon oxide film on the silicon wafer by means of high-temperatureoxidation. By oxidizing the silicon wafer top form silicon oxide (SiO₂),a compressive stress is generated in the silicon oxide, and a top Si islaminated on the silicon oxide. The SOI wafer (top Si/SiO₂/lower bulkSi) is simply patterned into a ribbon form, and the lower bulk siliconis etched to form a suspended silicon ribbon. At this time, as the lowersilicon to which silicon oxide belongs to is removed, the compressivestress is relieved, and silicon in the upper material region receives atensile stress. Since the suspended Si ribbon contains silicon oxide ina lower portion thereof, a tensile stress is also included therein, andthe stress is maintained after transferring, thereby ensuring improvedmobility.

The silicon wafer formed on the insulator may be various kinds of wafersused at the present for various purposes, and this may also be appliedto other kinds of laminated wafers having a residual stress. If only asacrificial layer at a lower portion is etched for implementing asuspended form, a suspended membrane may be easily formed. In case ofthe silicon ribbon, a deformation ratio of about 0.2% is applied bymeans of the relieved compressive stress, and charge mobility increasesby about 15 to 20% when a TFT is manufactured. By using this method,charge mobility of not only silicon but also various materials may beimproved, and by means of the transferring process, not only a highperformance single device but also various circuits may be implementedin a flexible electronic device application. In addition, during thetransferring process, an automation system may be used, for example by aroll-transfer method, to allow rapid transfer to a large area, which mayreduce high manufacture costs of existing flexible devices based oninorganic materials.

FIG. 5 is a diagram showing a process of etching a bulk inorganic matteraccording to an embodiment of the present disclosure.

The bulk inorganic matter may be etched by means of two methods asfollows.

First, the bulk inorganic matter at the lower portion of the inorganicstressor may be etched from an upper portion of the inorganic stressor.As shown in FIG. 5a , an inorganic matter ribbon or the like may beformed, and then etching may be performed from an upper portion in alateral direction to form a suspended ribbon.

As another method, the bulk inorganic matter at the lower portion of theinorganic stressor may be etched from a lower portion of the bulkinorganic matter by means of dry etching. As shown in FIG. 5b , after adevice is manufactured on the inorganic wafer (SOI wafer), bulk siliconmay be removed from a lower portion of the bulk wafer by means ofgrinding and plasma dry etching to make a suspended Si device. If thismethod is used, SiO₂ at an intermediate portion may serve as an etchstopper in the plasma dry etching process, and a large suspended Sidevice may be easily manufactured. In this method, a suspended ribbonmay also be formed, and the same performance improvement may be ensured.

FIG. 6 shows an inorganic matter device having a tensile stressaccording to an embodiment of the present disclosure.

An inorganic material 610 transferred onto a substrate 620 is depicted.Here, the inorganic material 610 includes an inorganic stressor formedfrom an inorganic wafer made of an inorganic matter, and an inorganiclayer formed on the inorganic stressor to have a tensile stress. Also,the inorganic layer has a tensile stress by etching the bulk inorganicmatter to relieve a compressive stress applied to the inorganic stressorwhen the inorganic stressor is formed. The inorganic stressor may beformed by oxidizing or nitriding the inorganic wafer, or by depositing ametal or dielectrics on the inorganic wafer. The inorganic matter mayuse an inorganic matter such as silicon which allows oxidation andnitridation. In other case, another material having an internal residualstress may also be used. The inorganic material 610 having a tensilestress may be transferred to a substrate from a wafer made of theinorganic matter by means of a polydimethyl siloxane (PDMS) roller orthe like. The tensile stress of the inorganic layer may vary dependingon the thickness of the inorganic layer. The substrate may be a rigidsubstrate such as wafer, glass, metal foil or the like, or a polymersubstrate such as plastic and rubber.

A semiconductor material according to an embodiment of the presentdisclosure includes an inorganic material having a tensile stress. Theinorganic material having a tensile stress may be used instead ofvarious inorganic materials used for the semiconductor material.

The inorganic material 610 having a tensile stress has been describedabove in detail with reference to FIGS. 1 to 5, and is not explained indetail here.

FIG. 7 is a diagram showing a process of analyzing a mechanism ofmanufacturing an inorganic material having a tensile stress andanalyzing a stress thereof according to an embodiment of the presentdisclosure.

As an embodiment of the present disclosure, a process of manufacturingan organic material having a tensile stress and analyzing itscharacteristics is illustrated. First, a ribbon-type silicon pattern isformed on a SOI wafer. At this time, a compressive stress is present atan intermediate silicon oxide layer. After that, a suspended (capable ofself-supporting) silicon ribbon is formed by etching a lower portion ofthe bulk silicon. At this time, as a compressive stress in the siliconoxide is relieved, a length increases, and a tensile stress is appliedto an upper silicon ribbon. Even though this is transferred onto a PETsubstrate, the tensile stress applied to the upper silicon ismaintained.

FIG. 8 shows an analysis result by a Raman spectroscopy, showing atensile stress of an inorganic material according to an embodiment ofthe present disclosure. Here, (a) shows locations of suspendedsilicon/silicon oxide ribbon and silicon/silicon oxide ribbontransferred onto the PET substrate. (b) shows a Raman pick location ofeach location, in which locations of the suspended silicon pick and thetransferred silicon pick are moved to the left in comparison to the bulksilicon and the anchor portion, which means that a tensile stress isapplied. (c) is a graph showing a changing amount of tensile stressaccording to the thickness of a top Si, measured by a Ramanspectroscopy, in which it may be found that an amount of stressincreases as the thickness of the top Si is smaller. In (d), thecalculated values and the measured values are compared.

FIG. 9 shows a process of transferring a silicon FET device having atensile stress according to an embodiment of the present disclosure to aplastic substrate by means of roll-transfer printing. First, as shown in(a), a silicon wafer is oxidized to form silicon oxide, and then asilicon FET is formed on the wafer. After that, a suspended (capable ofself-supporting) silicon FET ribbon is formed by etching a lower portionof the bulk silicon. At this time, the silicon FET ribbon has a tensilestress. After that, in (9), the silicon FET ribbon is detached using aroller, and the silicon FET ribbon having a tensile stress istransferred onto the PET substrate to manufacture an inorganic matterdevice. (c) shows a sectional structure of the transferred silicon FETdevice having a tensile stress.

FIG. 10 shows electric characteristics of an inorganic matter devicehaving different tensile stresses depending on the thickness of uppersilicon according to an embodiment of the present disclosure.

In FIG. 10, (a) shows that electric characteristics of each thickness ofthe upper silicon of the silicon FET on a SOI wafer with respect to achannel having a width of 100 μm and a length of 10 μm at a drainvoltage of 0.1 V are converted into a linear log scale. As the thicknessof the upper silicon is smaller, a higher strain is applied to thesilicon so that the drain current increases. (b) shows outputcharacteristics of the silicon FET of the material measured in (a), at agate voltage of 0 V to 4 V, and shows that the drain current increasesas the thickness of silicon is smaller, similar to the above. (c) is agraph showing charge mobility of a material prepared based on theobtained electric characteristic curve, and it may be found that theincrease range of charge mobility is improved as the thickness of uppersilicon is smaller.

In FIG. 11(a) shows an automatic transferring machine and a structuralfront section of the automatic transferring machine, (b) shows an imageof broad-band flexible TET array located at the PET substrate, and (c)shows a histogram of mobility distribution measured from the broad-bandsilicon FET array.

While the exemplary embodiments have been shown and described, it willbe understood by those skilled in the art that various changes in formand details may be made thereto without departing from the spirit andscope of this disclosure as defined by the appended claims. In addition,many modifications can be made to adapt a particular situation ormaterial to the teachings of this disclosure without departing from theessential scope thereof.

Therefore, it is intended that this disclosure not be limited to theparticular exemplary embodiments disclosed as the best mode contemplatedfor carrying out this disclosure, but that this disclosure will includeall embodiments falling within the scope of the appended claims.

REFERENCE SYMBOLS

610: inorganic material

620: substrate

What is claimed is:
 1. An inorganic material having a tensile stress,comprising: an inorganic stressor formed from an inorganic wafer made ofan inorganic matter; and an inorganic layer formed on the inorganicstressor to have a tensile stress, wherein the inorganic layer has atensile stress by etching the bulk inorganic matter to relieve acompressive stress applied to the inorganic stressor when the inorganicstressor is being formed.
 2. The inorganic material having a tensilestress according to claim 1, wherein the inorganic stressor is formed byoxidizing or nitriding the inorganic wafer, or by depositing metal ordielectrics on the inorganic wafer.
 3. The inorganic material having atensile stress according to claim 1, further comprising: a substratelocated at a lower portion of the inorganic stressor.
 4. The inorganicmaterial having a tensile stress according to claim 3, wherein thesubstrate is any one of wafer, glass, metal foil and polymer substrates.5. The inorganic material having a tensile stress according to claim 1,wherein the inorganic matter is an inorganic matter which allowsoxidization and nitridation.
 6. The inorganic material having a tensilestress according to claim 1, wherein a tensile stress of the inorganiclayer varies depending on thickness or kind of the inorganic layer andthe inorganic stressor.
 7. A semiconductor device, comprising aninorganic material having a tensile stress according to claim 1.